1. Technical Field
The present disclosure relates to printed circuit boards that can save layout space on the printed circuit board.
2. Description of Related Art
Common-mode noise in signals is rejected by using differential signal transmission line pair that has a first transmission line and a second transmission line. When the differential signal transmission line pair routed on a printed circuit board (PCB), opposite ends of the differential signal transmission line pair are routed on an outer signal layer of the PCB, and middle portions of the differential signal transmission line pair are routed an inner signal layer of the PCB. The portions of the differential signal transmission line pair which are routed on the outer signal layer of the PCB are called microstrip lines. The portions of the differential signal transmission line pair which are routed on the inner signal layer of the PCB are called striplines.
Further, crosstalk is the electrical “noise” caused by mutual inductance and mutual capacitance between differential signal transmission line pairs, due to the close proximity of the differential signal transmission line pairs to each other. Crosstalk can cause digital system failure due to false signals appearing on a receiver. A typical layout method for reducing the crosstalk is to increase the distance between the two differential signal transmission line pairs, which occupies extra space and increases cost.
Therefore, there is room for improvement within the art.